S?4?UNITEDSTATESENVIRONMENTALPROTECTIONAGENCY0REGIONIll1650ArchStreet%Philadelphia,Pennsylvania19103-2029DEC092011TheHonorableVincentC.GrayMayoroftheDistrictofColumbia1350PennsylvaniaAvenue,N.W.Suite316Washington,D.C.20004DearMayorGray:ThankyouforyourMarch11,2009recommendationsonairqualitydesignationsfortherevised2008NationalAmbientAirQualityStandards(NAAQS)forozonethroughouttheDistrictofColumbia.IappreciatetheinformationtheDistrictofColumbiasharedwiththeU.S.EnvironmentalProtectionAgency(EPA)aswemoveforwardtoimproveozoneairquality.ThisletteristonotifyyouofEPA’spreliminaryresponsetotheDistrictofColumbia’srecommendationsandtoinformyouofourapproachforcompletingthedesignationsfortherevisedozonestandards.OnMarch12,2008,EPAreviseditsNAAQSforground-levelozonetoprovideincreasedprotectionofpublichealthandtheenvironment.EPAloweredtheprimary8-hourozonestandardfrom0.08partspermillion(ppm)to0.075ppmtoprotectagainsthealtheffectsassociatedwithozoneexposure,includingarangeofseriousrespiratoryillnessesandincreasedprematuredeathfromheartorlungdisease.EPArevisedthesecondary8-hourozonestandard,makingitidenticaltotheprimarystandard,toprotectagainstwelfareeffects,includingimpactsonsensitivevegetationandforestedecosystems.Historyshowsusthatbetterhealthandcleanerairgohand-in-handwitheconomicgrowth.Workingcloselywiththestatesandtribes,EPAisimplementingthestandardsusingacommonsenseapproachthatimprovesairqualityandminimizestheburdenonstateandlocalgovermnents.Aspartofthisroutineprocess,EPAisworkingwiththestatestoidentif’areasinthecountrythatmeetthestandardsandthosethatneedtotakestepstoreduceozonepollution.Withinoneyearafteraneworrevisedairqualitystandardisestablished,theCleanAirAct(CAA)requirestheGovernorofeachstatetosubmittoEPAalistofallareasinthestate,withrecommendationsforwhethereachareameetsthestandard.Asafirststepinimplementingthe2008ozonestandards,EPAaskedstatestosubmittheirdesignationrecommendations,includingappropriateareaboundaries,byMarch12,2009.InSeptember2009,EPAannounceditwasreconsideringthe2008ozonestandards.EPAlatertookstepstodelaythedesignationprocessforthe2008ozonestandardspendingoutcomeofthereconsideration.However,inSeptember2011,theOfficeofManagementandBudgetreturnedtoEPAthedraftfinalruleaddressingthereconsiderationofthe2008ozonestandards.OnSeptember22,2011,EPArestartedtheimplementationeffortbyissuingamemorandumtoclarifyforstateandlocalagenciesthestatusofthe2008ozonestandardsandtooutlineplansformovingforwardtoimplementthem.EPAindicatedthatitwouldproceedwithinitialareadesignationsforthe2008standards,andplannedtousetherecommendationsstatesmadein2009asupdatedbythemostcurrent,certifiedairqualitydatafrom2008-2010.WhileEPAdidnotrequestthatstatessubmitupdateddesignationrecommendations,theEPAprovidedtheopportunityforstatestodoso.AsrequiredbytheCAA,EPAwilldesignateanareaasnonattainmentifitisviolatingthe2008ozonestandardsorcontributingtoaviolationofthestandardsinanearbyarea.Consistentwithdesignationsforpreviousozonestandards,EPAintendstodesignateanareaasunclassifiable!attainmentiftherearecertified,quality-assuredairqualitymonitoringdatashowingtheareaismeetingtheozonestandardsoriftherearenomonitoringdataforthearea,andEPAhasnotmadeadeterminationthattheareaiscontributingtoaviolationinanearbyarea.AfterconsideringtheDistrictofColumbia’sMarch11,2009ozonedesignationrecommendationsandotherrelevanttechnicalinformation,including2008-2010airqualitydata,EPAintendstosupporttheDistrictofColumbia’srecommendedareadesignationandboundaryfortheWashington-DC-MD-VAarea.TheenclosedTechnicalSupportDocumentprovidesadetailedanalysistosupportourpreliminarydecisions.EPAwillcontinuetoworkwithDistrictofficialsregardingtheappropriateboundaryfortheareaintheDistrictofColumbia.IftheDistrictofColumbiahasadditionalinformationthattheDistrictwouldlikeEPAtoconsider,pleasesubmitittousbyFebruary29,2012.EPAwillalsomakeitspreliminarydesignationdecisionsandsupportingdocumentationavailabletothegeneralpublicforreviewandcomment.Wewillbeannouncinga30-daypubliccommentperiodshortlyintheFederalRegister.Afterconsideringadditionalinformationwereceive,EPAplanstopromulgatefinalozonedesignationsinspringof2012.EPAiscommittedtoworkingwiththestatesandtribestosharetheresponsibilityofreducingozoneairpollution.Currentandupcomingfederalstandardsandsafeguards,includingpollutionreductionrulesforpowerplants,vehiclesandfuels,willassuresteadyprogresstoreduceozoneformingpollutionandwillprotectpublichealthinCommunitiesacrossthecountry.Welookforwardtoacontinueddialoguewithyouandyourstaffasweworktogethertoimplementthe2008ozonestandards.Ifyouhaveanyquestions,pleasedonothesitatetocontactmeorhaveyourstaffcontactMs.ArnieHowell,EPA’sDistrictofColumbiaLiaison,at(215)814-5722.Enclosurecc:TheHonorableChristopheA.0.Tulou,DirectorM.GarvinSincerely,RegionalAdministratorDistrictDepartmentofEnvironment